The tripod is a device used for stabilizing the equipment such as cameras and video cameras to achieve a given photography and shooting result, which generally consists of a pan/tilt and a frame body, wherein the frame body consists of three support frames and one main frame. To facilitate the height adjustment of the pan/tilt, each support leg consists of a group of leg tubes adjusted and fixed by a hand button mechanism. As disclosed in China Patent Literature, this new invention is titled “A locking device for tripod leg tubes”, with an authorized notification No. of CN 201589047U and the authorized notification date of Sep. 22, 2011, such a tripod leg tube locking device consists of a threaded sleeve with one end connected to an upper tube, an inner wall on the other end and a lower tube forming a chamber with an open lower end. Such chamber is at least provided with a locking ring fitted on the lower tube. The aforesaid locking ring is provided with an opening and the aforesaid threaded sleeve is connected with the outside of the locking knob. Such a locking knob is provided with a shrink hole on its lower end to prevent the aforesaid locking ring from sliding away from the chamber. In the above-mentioned structure, the threaded sleeve has a poor locking force and poor structure stability. Besides, in existing similar products, the internal locking lining can easily come away and be displaced when the movable threaded sleeve and the fixed sleeve are completely disconnected, as a result of which, the locking lining is not located at its correct position when re-locking, thus resulting in the failure of the locking function.
Accordingly, there exists a need for a new and improved locking system for a tripod that overcomes at least one of the aforementioned disadvantages.